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Musical Fidelity Nu-Vista 300 power amplifier Measurements

Sidebar 3: Measurements

Before being measured, the big Musical Fidelity amplifier was warmed up for an hour driving a 1kHz sinewave at 1/3 power into 8 ohms. This will maximally stress a solid-state amplifier with a class-B output stage; after the 60 minutes of operation the amplifier's heatsinks were too hot to keep my hand on, implying a temperature of well above 60 degrees C.

The Nu-Vista didn't invert polarity, and its input impedance was a highish 64k ohms. The voltage gain into 8 ohms was 30dB, about 3dB higher than normal for a typical American amplifier, with a 0.08dB…

Musical Fidelity Nu-Vista 300 power amplifier Measurements part 2

Noise was low, the A-weighted S/N ratio (ref. 1W into 8 ohms) being a good 77.3dB. This figure worsened only slightly, to 71.4dB, with an unweighted, wideband measurement. Distortion levels on continuous tones were very low; I had to drive the amplifier at a high level (125W into 8 ohms) to extract the waveform of the distortion residual from the noise. This (fig.4) is mainly second harmonic. Some third harmonic appeared at 250W into 4 ohms, but at a very low level.

Fig.4 Musical Fidelity Nu-Vista 300, 1kHz waveform at 125W into 4 ohms (top), distortion and noise waveform with…

Musical Fidelity Nu-Vista 300 power amplifier Measurements part 3

The Musical Fidelity's output power plotted against the THD+noise percentage, on continuous tones with both channels driven, is shown in fig.8. The amplifier clipped (defined as 1% THD+N) at 305Wpc into 8 ohms (24.8dBW), with 480Wpc available into 4 ohms (23.8dBW) and 700W into 2 ohms (22.4dBW), the last two readings below the specified power. But it should be noted that, with this much power being delivered into the load, our lab's AC line voltage was drooping considerably. It was just 108V for the 2 ohm delivery, which will compromise the measured figure.

Fig.8 Musical Fidelity…

Musical Fidelity Nu-Vista 300 power amplifier Wes Phillips, June 2006

Wes Phillips auditioned the Nu-Vista 300 in June 2006 (Vol.29 No.6):

While I enjoyed the Moscode 401HR during its solo audition, I was freaking out a tad trying to imagine what I could compare it to when it came time to evaluate it against another amplifier of similar aspirations and/or price—one that had been reviewed in Stereophile and thus was a "known" quantity. Finally, the penny dropped and I realized that my own reference amp, the one I actually own and listen to when I don't have any deadlines, was a hybrid tube/solid-state device with a monster power supply and a retail price…

Musical Fidelity Nu-Vista 300 power amplifier Wes Phillips, September 2006

Wes Phillips, September 2006 (Vol.29 No.9

The surprise wasn't that a big, powerful monoblock had, um, power; the startling part was how subtly that power was employed. The natural comparison for the $3500/pair Portal Paladin seemed to be my reference power amp, the two-chassis Musical Fidelity Nu-Vista 300. Of course, the Nu-Vista isn't strictly speaking a monoblock—its two chassis are split into a power supply and a signal amplifier—and its limited edition of 500 units sold out long ago. On the other hand, John Atkinson called it back in 1999 "possibly the best-measuring amplifier I've…

Noise Pollution

"Imagine a lake," reads the website of the Noise Pollution Clearinghouse (NPC) , "filled with semi-tractor-trailer trucks, magically skimming across the water.

"Remarkably, such a lake would be quieter than if it was filled with motorized boats. Our lakes are governed by out of date, unenforceable regulations so lax that no state has boat noise limits lower than federal limits for tractor-trailer trucks (80 decibels at 50 feet). We are literally turning our lakes into the New Jersey Turnpike."

The NPC is a national nonprofit organization that seeks to, among other things, raise…

Graham Robin tonearm

The best tonearm I ever heard was a second-generation Mission Mechanic, ca 1986. It was mounted on a Roksan Xerxes turntable, and I spent several happy hours listening to records on that combination (with a low-compliance EMT cartridge) in two very different systems: one with solid-state amplification from DNM and Roksan's own dynamic Darius loudspeakers, and the other—my home system of the time—using tube amplification from Conrad-Johnson and a borrowed pair of Stax electrostatic speakers.

Skeptics of subjective reviewing will have found grist for their mills already: To them,…

Graham Robin tonearm Page 2

As I write this, I've tried the Robin on two turntables, each exemplary in its own way: the VPI Aries Scout, still here from its go-round for the February issue, and the Rega Planar 3. In the case of the former, the Graham took over from VPI's own JMW-9 tonearm, and in the case of the Rega...well, the comparison was the obvious one, irresistible as it was.

As noted above, and as I learned from experience, audiophiles who buy the Graham expressly for a Rega turntable get the same basic arm as everyone else, but with a few different bits: a shallower arm-mount collar sized for the Rega…

Graham Robin tonearm Page 3

Here, too, the Robin didn't have the best surface-noise performance I'd ever heard—but in fairness, neither does the RB-300. The major difference has to do with how the Rega arm gets right to the heart of the music on every record I play: It finds the line and sings it. The Robin didn't fail completely in this regard, but on the Rega player it simply wasn't as good—especially, I've found, with electric music. On Big Star's wonderful "Way Out West," for example (Radio City, Ardent ADS-1501), the Graham arm delivered the same big, deep bass I'd come to expect, given its performance with the…

Graham Robin tonearm Specifications

Sidebar 1: Specifications

Description: Pivoting tonearm with removable headshell. Effective length: 235mm. Effective mass: 11gm. Antiskating: calibrated spring.
Finish: Chrome (mostly).
Serial number of unit reviewed: Not given.
Price: $795 (at time review was written); $645 from April 2003. Approximate number of dealers: 50.
Manufacturer: Graham Engineering, Inc., 7233 Avalon Drive, Wilmington, MA 01887. Tel: (781) 932-8777. Web: www.concentric.net/~Tnv2001. US distributor: Musical Surroundings, 5856 College Avenue, Ste. 146, Oakland, CA 94618. Tel: (510) 420-0379. Fax: (510…